/*
 * Copyright 2006-2007 S W McIlroy
 * Licensed  under the  Apache License,  Version 2.0  (the "License");
 * you may not use  this file  except in  compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed  under the  License is distributed on an "AS IS" BASIS,
 * WITHOUT  WARRANTIES OR CONDITIONS  OF ANY KIND, either  express  or
 * implied.
 *
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.mockfu;

import java.util.Arrays;
import java.util.Iterator;
import java.util.Stack;

class MatcherIterator implements Iterator<Matcher<Object>>, Iterable<Matcher<Object>>
{

    private final Stack<Iterator<Matcher<Object>>> stack = new Stack<Iterator<Matcher<Object>>>();

    public MatcherIterator( Matcher<Object>... matchers )
    {
        stack.push( Arrays.asList( matchers ).iterator() );
    }

    public boolean hasNext()
    {
        return !stack.isEmpty() && stack.peek().hasNext();
    }

    public Matcher<Object> next()
    {
        Matcher<Object> next = stack.peek().next();
        if( !next.getNested().isEmpty() )
        {
            stack.push( next.getNested().iterator() );
        }

        while( !stack.isEmpty() && !stack.peek().hasNext() )
        {
            stack.pop();
        }

        return next;
    }

    public void remove()
    {
        throw new UnsupportedOperationException( "Cannot remove matchers" );
    }

    public Iterator<Matcher<Object>> iterator()
    {
        return this;
    }
}
